It is often desirable with domestic animals (e.g. cattle, swine, chickens) to implant into the animals a solid or semi-solid medicament. Such practice is common, for example, for growth stimulation of cattle and swine. Typically, growth stimulating hormones are implanted in the neck or ear of the animal, to remain there for an extended period of time. Because the ear is a throwaway organ, it is a preferred implantation site. Any implate residue present in the ear at slaughter will not enter channels of commerce to become ingested by humans or domestic animals.
A typical medicament implanter device comprises a hand-held instrument built of a size consistent with the size of the animal (large for cattle, small for chickens). The body of the instrument is typically shaped either like a handgun, or alternatively, like a large hypodermic syringe with a receive-dispenser for the medicament implant. Both types use an apertured needle to make a sizable non-coring puncture opening into the skin (e.g. of the ear) of the animal and form a cavity in the skin occupied temporarily by the needle of the instrument.
U.S. Pat. Nos. 4,531,938 issued to Kay et al., 4,451,254 issued to Dinius et al., and 2,761,446 issued to Reed are representative of syringe type implanters. U.S. Pat. Nos. 3,774,607 issued to Schmitz, 4,576,591 issued to Kay et al., 4,447,223 issued to Kay et al., and 4,400,170 issued to McNaughton et al. are representative of handgun type implanters.
In a common handgun-type implanter such as that describe in U.S. Pat. No. 3,774,607 ('607 patent), which is herein incorporated by reference, the medicament implants are purchased already loaded into a cartridge. That is, the cartridge is purchased fully loaded and is disposed of when all of the implants have been used. Unfortunately, with such cartridges the framer is forced to purchase a minimum number of implants (the cartridge in the illustrated model of the '607 patent contains 24 pellets), which may be considerably more than he wishes to purchase. Furthermore, the handgun-type implanter of the '607 patent only allows use of circular, cylinder-type cartridges. Therefore, farmers who might prefer strip cartridges, have no choice but to use the standard cylinder-type cartridge with its relatively large number of doses.